The invention is based on a radiator blower, in particular for motor vehicles, according to the preamble of claim 1.
Radiator blowers are used in motor vehicles that comprise at least two separate individual fans to cover a large demand for cooling, which said fans are operated either to ventilate the radiator of the internal combustion engine evenly, or to ventilate the radiator of the internal combustion engine and an air conditioner separately within a common circuit configuration that makes it possible to turn on either just one of the individual fans or both individual fans in series or in parallel.
When such radiator blowers come to rest after being turned off, they generate noise that is not inconsiderable, because the individual fans pass through various resonant frequencies that, depending on excitation, can result in disturbing tonal magnifications in the noise spectrum. The tonal magnifications are perceived as being very unpleasant in particular when an internal combustion engine is running at idle and producing little noise, or when the internal combustion engine is switched off.